Tom,
We have also talked about solving the multi-column statistics problem
(which, at its core, is which combinations of columns are worth
accumulating stats for? --- you can't possibly store stats for every
combination!) by having what would amount to hints from the DBA saying
keep stats
On Wed, Oct 11, 2006 at 03:08:42PM -0700, Ron Mayer wrote:
Is one example is the table of addresses clustered by zip-code
and indexes on State, City, County, etc?
No.
Now I'm not saying that a more advanced statistics system
couldn't one-day be written that sees these patterns in the
data
On Thu, Oct 12, 2006 at 08:34:45AM +0200, Florian Weimer wrote:
Some statistics are very hard to gather from a sample, e.g. the number
of distinct values in a column.
Then how can the DBA know it, either? The problem with this sort of
argument is always that people are claiming some special
On Oct 12, 2006, at 4:26 AM, Andrew Sullivan wrote:
On Thu, Oct 12, 2006 at 08:34:45AM +0200, Florian Weimer wrote:
Some statistics are very hard to gather from a sample, e.g. the
number
of distinct values in a column.
Then how can the DBA know it, either? The problem with this sort of
Casey Duncan [EMAIL PROTECTED] writes:
Yes, but it may be much more efficient for the human to tell the
computer than for the computer to introspect things. Take, for
example, ndisinct as data grows large.
Yeah, an override estimate for a column's ndistinct seems a perfect
example of the
Tom Lane wrote:
We have also talked about solving the multi-column statistics problem
(which, at its core, is which combinations of columns are worth
accumulating stats for? --- you can't possibly store stats for every
combination!) by having what would amount to hints from the DBA saying
